Confirmatory analysis of steroids in muscle using liquid chromatography-tandem mass spectrometry

A method is described for screening and confirmation of synthetic and endogenous steroids in muscle tissue. The method is sensitive, selective, and rapid and the consumption of organic solvents is low, compared to previously published methods. The procedure involves hydrolysis, defattening with heptane and final clean up with SPE using C(18) cartridge. After filtration, the analytes are analysed by LC/MS/MS and quantification is performed using deuterated internal standards. Decision limits (CC alpha) varied from 0.02 to 0.33 mu g kg(-1) and the detection capabilities (CC beta) were <0.50 mu g kg(-1). The mean within-laboratory reproducibility ranged 5-22% (%RSD(IR)). Endogenous steroids (e. g. testosterone, epitestosterone and androstenedione) have been included in the method, to provide an insight into their levels, as the presence of these steroids was detected several times during analysis of imported meat.